1. Technical Field
The present disclosure relates in general to wireless communication devices and in particular to receiver synchronization in wireless communication devices.
2. Description of the Related Art
Many wireless communication devices are capable of operating in different modes using different network communication standards such as Global System for Mobile Communications (GSM), Code Division Multiple Access (CDMA), and Long Term Evolution (LTE). To maximize use of the limited real estate within these devices, the devices are configured to switch operation between communication modes using a same set of transceiver components. However, these devices have a challenge of maintaining receiver synchronization between the baseband modem and a radio frequency integrated circuit (RFIC). This challenge of maintaining synchronization can often be associated with initiating communication operation following a sleep mode or after a power up procedure. Furthermore, in order to use common RF components to reduce power and area requirements, the RFIC sampling rate may differ from a baseband modem sampling rate. A phase locked status associated with modem timing recovery can be lost if a receiver's timing shifts by more than a specific fraction of the cycle period associated with the corresponding receiver sampling rate. For example, phase locked status can be lost if the receiver's timing shifts by more than the one quarter of the baseband cycle period for a number of CDMA based technologies. In addition, wireless communication devices generally use an asynchronous digital radio frequency interface as a standard communication interface between the baseband modem and the RFIC. However, the time interval between an RFIC sampling of an over-the-air signal and an arrival of corresponding data into the baseband First In First Out (FIFO) buffer after transmission over the asynchronous digital radio frequency communication interface is not fixed.